Sensitive control of N2O emissions and microbial community dynamics by organic fertilizer and soil interactions

Greenhouse Gas Balances and Yield-Scaled Emissions for Storage and Field Application of Organic Fertilizers Derived from Cattle Manure

“…There were no clear differences in soil gravimetric water content, which averaged 20-22 % in soil samples from all manure-derived fertilizers during the first six weeks, corresponding to 50-55 % WFPS in this soil (Li et al, 2015). A recent laboratory study concluded that the interactions between liquid organic fertilizers and the soil are critical for N 2 O emissions (Meng et al, 2022), and greater redistribution of N and labile C with infiltrating water may trigger higher N 2 O emissions. Pools of NH 4 + and NO 3 in treatments with mineral fertilizer remained at the same high level until the time when N uptake by spring barley was expected, indicating that dissolution of inorganic N and subsequent nitrification were slow.…”

“…The crop yield of the control treatment M0 was significantly lower than that of fertilized treatments (p < 0.05), but there were no significant differences in crop yields among fertilized treatments, thus environmental losses were generally independent of fertilizer type or composition. Nitrification has been considered the main source of N 2 O emissions from the soil below 60% WFPS (Davidson (1993), but Meng et al (2022) used 15 N to study sources of N 2 O with the same organic fertilizers and soil as this study at 55% WFPS, and the results showed that denitrification was the main source of N 2 O; thus coupled nitrification-denitrification may have contributed to N 2 O emissions (Petersen et al, 1991). Since crop N uptake was similar to mineral and organic fertilizers, any N immobilization was probably re-mineralized during the spring period.…”

“…A review by Möller (2015) concluded that the predominant response to anaerobic digestion of manure is a reduction of N 2 O emissions after field application, possibly as a result of the lower availability of degradable carbon to maintain anaerobic conditions supporting denitrification (Baral et al, 2016). There is little information about the possible effect of separating digestate on soil N 2 O emissions; (Meng et al, 2022) found in laboratory incubation experiments, surprisingly, higher N 2 O emissions from the liquid fraction and concluded that denitrification was enhanced by the greater contact between the liquid fraction and soil.…”

Short-Term Nitrous Oxide Emissions from Cattle Slurry for Silage Maize: Effects of Placement and the Nitrification Inhibitor 3,4-Dimethylpyrazole Phosphate (DMPP)

“…During June the emission of N2O from placed slurry treated with DMPP was significantly higher than from untreated slurry (Figure 7). Denitrification has been found to be the main source of N2O emissions from soil amended with cattle slurry (Meng et al, 2022), but the distribution and average concentrations of NO3 -were similar in placed slurry with and without Vizura®. We propose that the higher N2O emissions were due to nitrification activity taking place in close association with the slurry treated with Vizura®.…”

Natural regeneration or tree planting in a tropical forest‐to‐pasture damaged area: which is more efficacious for soil ecosystem recovery?

“…Studies have shown that increases in leaf litter enhance the N input into soils resulting in decreases in decomposition rates as more TOC is converted into microbial biomass, and potentially reducing the levels of TOC development (Miao et al 2019; Ma et al 2020; Zhu et al 2021; Meng et al 2022). The greater abundance of Fabaceae trees in the LCPL site could have facilitated a greater rate of inorganic N input into the soils, decreasing the decomposition rate, resulting in the lower respiration and TOC levels observed in the LCPL versus the LCNR soils.…”